I spend this weekend reading thru my java book.
Today I have been searching the internet for things that I needed in java. Collision is build into java. I still have to search for more performance information.
Java has Area collision detection. You can use polygon area's to check collisions with.
I also searched for image manipulation methods. setrgb and getrgb can be used to modify bufferedimages. There are also faster ways that got to do with rasters.